458 DR JOHN ALEXANDER SMITH ON CALAMOICHTHYS, 



of inquiry to learn whether the different Orders and Genera of the Ganoids of 

 the ancient world, those found fossil in our rocks, and taken cognisance of by 

 the geologist, bore any similar relation to the rivers and their estuaries, and to 

 the seas or salt waters of the Pre-Adamic earth. Judging of the past by the 

 analogy of the present, it might almost be expected that the ancient Ganoids 

 would bear a somewhat corresponding relation to the fresh and salt waters of 

 their day, as is known to be the case with their living representatives in ours. 

 Accordingly, it does certainly appear, in this country more especially, that numer- 

 ous fossil remains of Ganoid fish have been found in formations that seem to point 

 to a fiuviatile, or at least an estuarine character and origin; and should there be 

 any truth in the analogy, the presence of these fish would form a valuable addi- 

 tional element towards determining the character of any rock formation. 



Only some six species of Polypterus have as yet been observed, and of these 

 four belong, it is said, to the river s} 7 stem of the Nile; another to Senegal 

 and proceeding still farther south along the western coast of Africa, we find a 

 sixth species, which has been discovered in the rivers of Cape Palmas. 



The specimens of fish sent from Old Calabar seemed, however, to differ con- 

 siderably from all the species of the genus Polypterus, in various important charac- 

 ters to be afterwards detailed, and especially in the very elongated form of the 

 body, and in the apparent total absence of ventral fins, which, however, from the 

 imperfect state of the specimens, could not be conclusively determined. 



While waiting, therefore, for more perfect specimens to settle definitely the 

 question of the absence of the ventral fins, I exhibited the mutilated fish at a 

 meeting of the Royal Physical Society, held on the 22d March 1865, and stated 

 that all the species of the genus Polypterus seemed to bear a close resemblance to 

 each other, in the general form of their comparatively short and fish-like body, 

 and in the presence of ventral fins, forming thus a very natural group or genus. 

 While the new fish, with its much elongated and more cylindrical form of body, 

 and apparently the entire absence of ventral fins, suggested at least the probabi- 

 lity of the existence, nearer the equator, of another allied but distinct group 

 of these African fish. I would therefore place this fish provisionally in a 

 new genus, which, from its general reptile or serpent-like aspect and form, I 

 would designate Erpetoichthys* (Ep-Trerov I^'?) — the reptile or serpent-fish; and 

 following the example of those Naturalists who have given the name of the loca- 

 lity where the fish was taken, to some of the species of Polypterus, I gave to this 

 new fish the specific name of E. calcibavims. 



I wrote to the Rev. Mr Robb, informing him of the very interesting nature of 



* I have since learned that this designation, or a closely allied one, has been already used in 

 Ichthyology, and accordingly, on the recommendation of Dr Grunther of the British Museum, I 

 have changed the name of the genus to Calamoichthys (KaXa/zog a reed, and I^ig, a fish), which 

 will still bear a relation to the cylindrical character of the fish. — J. A. S. 



